Project Background
During labor, the cervix undergoes effacement and dilation, where it thins and widens, facilitating delivery of the fetus. There are three stages of labor: 1. Effacement and dilation of cervix, 2. Delivery of fetus, and 3. Expulsion of the placenta (Evbuomwan & Chowdhury, 2023). The first stage is further divided into a latent and active phase, which are defined by the dilation of the cervix. From 0-6 cm, labor is in the latent dilation phase, and from 6-10 cm, labor is in the active dilation phase. In the latent phase, labor generally progresses slowly, which can be distressing for nulliparous women (Evbuomwan & Chowdhury, 2023). In the active phase, cervical exams are performed every 4 hours to ensure that labor is progressing at a suitable rate, generally 1 cm every 2 hours (Thornton et al., 2020). If labor does not appear to be progressing, various clinical strategies can be employed, such as pharmacologic or mechanical methods of cervical ripening (Evbuomwan & Chowdhury, 2023).
Need Statement
There is a need to objectively monitor cervical dilation for people in labor to prevent numerous inconsistent and invasive exams, increase accuracy of measurements, gain a more accurate understanding of labor progress and cultivate a more comfortable patient experience.
Existing Solutions
The current gold standard of cervical dilation measurement during labor is known as the digital method. This involves a practitioner inserting their fingers into the cervical opening to estimate cervical dilation based on the distance between their fingers, shown below. This process is subject to change based on the practitioner checking, their level of knowledge, and the size of their hands. Simulated measurement tests have shown that the digital method is only 54-56% correct to the centimeter using a hard model (Huhn & Brost, 2004; Phelps et al., 1995). However, the cervix is soft and the accuracy of measurements on soft models is significantly less at 19% (Huhn & Brost, 2004). Furthermore, intraobserver variability in simulated measurements has been reported as high as 52.1% (Phelps et al., 1995).
Beyond the inaccuracy of these exams, the process is invasive and can be extremely uncomfortable for the patient. Due to the subjectivity of the test, multiple doctors and nurses may have to check a cervix to determine its dilation, which increases the discomfort of the patient. Testing occurs intermittently during labor, as a measurement can only be taken when the clinician performs an exam, which can be hours apart. Because cervical dilation is not a linear process, noncontinuous measurement can lead to inaccurate prediction of labor outcomes. The digital method is the most widely used clinical solution by far.
Proposed Solution and Prototype
Patent Pending